Sodium Sulfate → HCID 86738223, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 3.12 g of cis-1-ethoxycarbonyl-3-phenyl-4-(4-tolyloxy)piperidine in 55 ml of anhydrous tetrahydrofuran is added dropwise under nitrogen to a suspension of 1.05 g of lithium aluminum hydride in 55 ml of tetrahydrofuran. The resulting mixture is refluxed for 2 hours, cooled to 5° C. and diluted with 100 ml of anhydrous ether. Saturated sodium sulfate solution is added dropwise with cooling until a flocculent white precipitate forms. The solid is filtered, washed with ether, and the filtrate is concentrated in vacuo to a colorless oil. The oil is dissolved in 150 ml of ether, washed with 100 ml of saturated sodium chloride solution, dried over anhydrous sodium sulfate, and concentrated in vacuo to afford a colorless oil. This oil is dissolved in ether (100 ml) and treated dropwise with a solution of 1.12 g of fumaric acid in a mixture of ether (100 ml) and ethanol (25 ml). The solvent is removed in vacuo, and the residue is triturated into solid with ether. The crystalline solid is filtered, washed with ether and dried. The filtrate is concentrated in vacuo to an oil and 1 ml of ethanol is added followed by approximately 5 ml of ether. The solution is seeded with the crystalline solid and another 5 ml of ether is slowly added. The solution is scratched to afford a second crop of salt. The two crops are combined and recrystallized by dissolving in 100 ml of boiling ethyl acetate, filtering the solution hot and boiling the filtrate down to a volume of 50 ml. The solid is filtered, washed with ethyl acetate and ether and dried to afford product as colorless crystals, mp 148°-150° C.

Provenance & Evidence